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author | Dimitry Andric <dim@FreeBSD.org> | 2014-11-24 09:08:18 +0000 |
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committer | Dimitry Andric <dim@FreeBSD.org> | 2014-11-24 09:08:18 +0000 |
commit | 5ca98fd98791947eba83a1ed3f2c8191ef7afa6c (patch) | |
tree | f5944309621cee4fe0976be6f9ac619b7ebfc4c2 /lib/CodeGen/PrologEpilogInserter.cpp | |
parent | 68bcb7db193e4bc81430063148253d30a791023e (diff) | |
download | src-5ca98fd98791947eba83a1ed3f2c8191ef7afa6c.tar.gz src-5ca98fd98791947eba83a1ed3f2c8191ef7afa6c.zip |
Vendor import of llvm RELEASE_350/final tag r216957 (effectively, 3.5.0 release):vendor/llvm/llvm-release_350-r216957
Notes
Notes:
svn path=/vendor/llvm/dist/; revision=274955
svn path=/vendor/llvm/llvm-release_35-r216957/; revision=274956; tag=vendor/llvm/llvm-release_350-r216957
Diffstat (limited to 'lib/CodeGen/PrologEpilogInserter.cpp')
-rw-r--r-- | lib/CodeGen/PrologEpilogInserter.cpp | 185 |
1 files changed, 120 insertions, 65 deletions
diff --git a/lib/CodeGen/PrologEpilogInserter.cpp b/lib/CodeGen/PrologEpilogInserter.cpp index b0e494ffcdc0..b98d210e9d57 100644 --- a/lib/CodeGen/PrologEpilogInserter.cpp +++ b/lib/CodeGen/PrologEpilogInserter.cpp @@ -16,10 +16,10 @@ // //===----------------------------------------------------------------------===// -#define DEBUG_TYPE "pei" #include "PrologEpilogInserter.h" #include "llvm/ADT/IndexedMap.h" #include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/SetVector.h" #include "llvm/ADT/SmallSet.h" #include "llvm/ADT/Statistic.h" #include "llvm/CodeGen/MachineDominators.h" @@ -29,7 +29,10 @@ #include "llvm/CodeGen/MachineModuleInfo.h" #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/RegisterScavenging.h" +#include "llvm/CodeGen/StackProtector.h" +#include "llvm/IR/DiagnosticInfo.h" #include "llvm/IR/InlineAsm.h" +#include "llvm/IR/LLVMContext.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/Compiler.h" #include "llvm/Support/Debug.h" @@ -42,6 +45,8 @@ using namespace llvm; +#define DEBUG_TYPE "pei" + char PEI::ID = 0; char &llvm::PrologEpilogCodeInserterID = PEI::ID; @@ -54,6 +59,7 @@ INITIALIZE_PASS_BEGIN(PEI, "prologepilog", "Prologue/Epilogue Insertion", false, false) INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo) INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree) +INITIALIZE_PASS_DEPENDENCY(StackProtector) INITIALIZE_PASS_DEPENDENCY(TargetPassConfig) INITIALIZE_PASS_END(PEI, "prologepilog", "Prologue/Epilogue Insertion & Frame Finalization", @@ -67,6 +73,7 @@ void PEI::getAnalysisUsage(AnalysisUsage &AU) const { AU.setPreservesCFG(); AU.addPreserved<MachineLoopInfo>(); AU.addPreserved<MachineDominatorTree>(); + AU.addRequired<StackProtector>(); AU.addRequired<TargetPassConfig>(); MachineFunctionPass::getAnalysisUsage(AU); } @@ -95,6 +102,9 @@ void PEI::calculateSets(MachineFunction &Fn) { return; } +/// StackObjSet - A set of stack object indexes +typedef SmallSetVector<int, 8> StackObjSet; + /// runOnMachineFunction - Insert prolog/epilog code and replace abstract /// frame indexes with appropriate references. /// @@ -105,7 +115,7 @@ bool PEI::runOnMachineFunction(MachineFunction &Fn) { assert(!Fn.getRegInfo().getNumVirtRegs() && "Regalloc must assign all vregs"); - RS = TRI->requiresRegisterScavenging(Fn) ? new RegScavenger() : NULL; + RS = TRI->requiresRegisterScavenging(Fn) ? new RegScavenger() : nullptr; FrameIndexVirtualScavenging = TRI->requiresFrameIndexScavenging(Fn); // Calculate the MaxCallFrameSize and AdjustsStack variables for the @@ -150,7 +160,7 @@ bool PEI::runOnMachineFunction(MachineFunction &Fn) { replaceFrameIndices(Fn); // If register scavenging is needed, as we've enabled doing it as a - // post-pass, scavenge the virtual registers that frame index elimiation + // post-pass, scavenge the virtual registers that frame index elimination // inserted. if (TRI->requiresRegisterScavenging(Fn) && FrameIndexVirtualScavenging) scavengeFrameVirtualRegs(Fn); @@ -160,10 +170,11 @@ bool PEI::runOnMachineFunction(MachineFunction &Fn) { // Warn on stack size when we exceeds the given limit. MachineFrameInfo *MFI = Fn.getFrameInfo(); - if (WarnStackSize.getNumOccurrences() > 0 && - WarnStackSize < MFI->getStackSize()) - errs() << "warning: Stack size limit exceeded (" << MFI->getStackSize() - << ") in " << Fn.getName() << ".\n"; + uint64_t StackSize = MFI->getStackSize(); + if (WarnStackSize.getNumOccurrences() > 0 && WarnStackSize < StackSize) { + DiagnosticInfoStackSize DiagStackSize(*F, StackSize); + F->getContext().diagnose(DiagStackSize); + } delete RS; ReturnBlocks.clear(); @@ -233,14 +244,14 @@ void PEI::calculateCalleeSavedRegisters(MachineFunction &F) { MachineFrameInfo *MFI = F.getFrameInfo(); // Get the callee saved register list... - const uint16_t *CSRegs = RegInfo->getCalleeSavedRegs(&F); + const MCPhysReg *CSRegs = RegInfo->getCalleeSavedRegs(&F); // These are used to keep track the callee-save area. Initialize them. MinCSFrameIndex = INT_MAX; MaxCSFrameIndex = 0; // Early exit for targets which have no callee saved registers. - if (CSRegs == 0 || CSRegs[0] == 0) + if (!CSRegs || CSRegs[0] == 0) return; // In Naked functions we aren't going to save any registers. @@ -257,51 +268,56 @@ void PEI::calculateCalleeSavedRegisters(MachineFunction &F) { } } - if (CSI.empty()) - return; // Early exit if no callee saved registers are modified! + if (!TFI->assignCalleeSavedSpillSlots(F, RegInfo, CSI)) { + // If target doesn't implement this, use generic code. - unsigned NumFixedSpillSlots; - const TargetFrameLowering::SpillSlot *FixedSpillSlots = - TFI->getCalleeSavedSpillSlots(NumFixedSpillSlots); + if (CSI.empty()) + return; // Early exit if no callee saved registers are modified! - // Now that we know which registers need to be saved and restored, allocate - // stack slots for them. - for (std::vector<CalleeSavedInfo>::iterator - I = CSI.begin(), E = CSI.end(); I != E; ++I) { - unsigned Reg = I->getReg(); - const TargetRegisterClass *RC = RegInfo->getMinimalPhysRegClass(Reg); + unsigned NumFixedSpillSlots; + const TargetFrameLowering::SpillSlot *FixedSpillSlots = + TFI->getCalleeSavedSpillSlots(NumFixedSpillSlots); - int FrameIdx; - if (RegInfo->hasReservedSpillSlot(F, Reg, FrameIdx)) { - I->setFrameIdx(FrameIdx); - continue; - } + // Now that we know which registers need to be saved and restored, allocate + // stack slots for them. + for (std::vector<CalleeSavedInfo>::iterator I = CSI.begin(), E = CSI.end(); + I != E; ++I) { + unsigned Reg = I->getReg(); + const TargetRegisterClass *RC = RegInfo->getMinimalPhysRegClass(Reg); - // Check to see if this physreg must be spilled to a particular stack slot - // on this target. - const TargetFrameLowering::SpillSlot *FixedSlot = FixedSpillSlots; - while (FixedSlot != FixedSpillSlots+NumFixedSpillSlots && - FixedSlot->Reg != Reg) - ++FixedSlot; - - if (FixedSlot == FixedSpillSlots + NumFixedSpillSlots) { - // Nope, just spill it anywhere convenient. - unsigned Align = RC->getAlignment(); - unsigned StackAlign = TFI->getStackAlignment(); - - // We may not be able to satisfy the desired alignment specification of - // the TargetRegisterClass if the stack alignment is smaller. Use the - // min. - Align = std::min(Align, StackAlign); - FrameIdx = MFI->CreateStackObject(RC->getSize(), Align, true); - if ((unsigned)FrameIdx < MinCSFrameIndex) MinCSFrameIndex = FrameIdx; - if ((unsigned)FrameIdx > MaxCSFrameIndex) MaxCSFrameIndex = FrameIdx; - } else { - // Spill it to the stack where we must. - FrameIdx = MFI->CreateFixedObject(RC->getSize(), FixedSlot->Offset, true); - } + int FrameIdx; + if (RegInfo->hasReservedSpillSlot(F, Reg, FrameIdx)) { + I->setFrameIdx(FrameIdx); + continue; + } + + // Check to see if this physreg must be spilled to a particular stack slot + // on this target. + const TargetFrameLowering::SpillSlot *FixedSlot = FixedSpillSlots; + while (FixedSlot != FixedSpillSlots + NumFixedSpillSlots && + FixedSlot->Reg != Reg) + ++FixedSlot; + + if (FixedSlot == FixedSpillSlots + NumFixedSpillSlots) { + // Nope, just spill it anywhere convenient. + unsigned Align = RC->getAlignment(); + unsigned StackAlign = TFI->getStackAlignment(); + + // We may not be able to satisfy the desired alignment specification of + // the TargetRegisterClass if the stack alignment is smaller. Use the + // min. + Align = std::min(Align, StackAlign); + FrameIdx = MFI->CreateStackObject(RC->getSize(), Align, true); + if ((unsigned)FrameIdx < MinCSFrameIndex) MinCSFrameIndex = FrameIdx; + if ((unsigned)FrameIdx > MaxCSFrameIndex) MaxCSFrameIndex = FrameIdx; + } else { + // Spill it to the stack where we must. + FrameIdx = + MFI->CreateFixedSpillStackObject(RC->getSize(), FixedSlot->Offset); + } - I->setFrameIdx(FrameIdx); + I->setFrameIdx(FrameIdx); + } } MFI->setCalleeSavedInfo(CSI); @@ -409,11 +425,28 @@ AdjustStackOffset(MachineFrameInfo *MFI, int FrameIdx, } } +/// AssignProtectedObjSet - Helper function to assign large stack objects (i.e., +/// those required to be close to the Stack Protector) to stack offsets. +static void +AssignProtectedObjSet(const StackObjSet &UnassignedObjs, + SmallSet<int, 16> &ProtectedObjs, + MachineFrameInfo *MFI, bool StackGrowsDown, + int64_t &Offset, unsigned &MaxAlign) { + + for (StackObjSet::const_iterator I = UnassignedObjs.begin(), + E = UnassignedObjs.end(); I != E; ++I) { + int i = *I; + AdjustStackOffset(MFI, i, StackGrowsDown, Offset, MaxAlign); + ProtectedObjs.insert(i); + } +} + /// calculateFrameObjectOffsets - Calculate actual frame offsets for all of the /// abstract stack objects. /// void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) { const TargetFrameLowering &TFI = *Fn.getTarget().getFrameLowering(); + StackProtector *SP = &getAnalysis<StackProtector>(); bool StackGrowsDown = TFI.getStackGrowthDirection() == TargetFrameLowering::StackGrowsDown; @@ -523,8 +556,12 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) { // Make sure that the stack protector comes before the local variables on the // stack. - SmallSet<int, 16> LargeStackObjs; + SmallSet<int, 16> ProtectedObjs; if (MFI->getStackProtectorIndex() >= 0) { + StackObjSet LargeArrayObjs; + StackObjSet SmallArrayObjs; + StackObjSet AddrOfObjs; + AdjustStackOffset(MFI, MFI->getStackProtectorIndex(), StackGrowsDown, Offset, MaxAlign); @@ -541,12 +578,29 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) { continue; if (MFI->getStackProtectorIndex() == (int)i) continue; - if (!MFI->MayNeedStackProtector(i)) - continue; - AdjustStackOffset(MFI, i, StackGrowsDown, Offset, MaxAlign); - LargeStackObjs.insert(i); + switch (SP->getSSPLayout(MFI->getObjectAllocation(i))) { + case StackProtector::SSPLK_None: + continue; + case StackProtector::SSPLK_SmallArray: + SmallArrayObjs.insert(i); + continue; + case StackProtector::SSPLK_AddrOf: + AddrOfObjs.insert(i); + continue; + case StackProtector::SSPLK_LargeArray: + LargeArrayObjs.insert(i); + continue; + } + llvm_unreachable("Unexpected SSPLayoutKind."); } + + AssignProtectedObjSet(LargeArrayObjs, ProtectedObjs, MFI, StackGrowsDown, + Offset, MaxAlign); + AssignProtectedObjSet(SmallArrayObjs, ProtectedObjs, MFI, StackGrowsDown, + Offset, MaxAlign); + AssignProtectedObjSet(AddrOfObjs, ProtectedObjs, MFI, StackGrowsDown, + Offset, MaxAlign); } // Then assign frame offsets to stack objects that are not used to spill @@ -563,7 +617,7 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) { continue; if (MFI->getStackProtectorIndex() == (int)i) continue; - if (LargeStackObjs.count(i)) + if (ProtectedObjs.count(i)) continue; AdjustStackOffset(MFI, i, StackGrowsDown, Offset, MaxAlign); @@ -632,7 +686,7 @@ void PEI::insertPrologEpilogCode(MachineFunction &Fn) { // we've been asked for it. This, when linked with a runtime with support // for segmented stacks (libgcc is one), will result in allocating stack // space in small chunks instead of one large contiguous block. - if (Fn.getTarget().Options.EnableSegmentedStacks) + if (Fn.shouldSplitStack()) TFI.adjustForSegmentedStacks(Fn); // Emit additional code that is required to explicitly handle the stack in @@ -711,14 +765,14 @@ void PEI::replaceFrameIndices(MachineBasicBlock *BB, MachineFunction &Fn, SPAdj += Size; MachineBasicBlock::iterator PrevI = BB->end(); - if (I != BB->begin()) PrevI = prior(I); + if (I != BB->begin()) PrevI = std::prev(I); TFI->eliminateCallFramePseudoInstr(Fn, *BB, I); // Visit the instructions created by eliminateCallFramePseudoInstr(). if (PrevI == BB->end()) I = BB->begin(); // The replaced instr was the first in the block. else - I = llvm::next(PrevI); + I = std::next(PrevI); continue; } @@ -757,7 +811,7 @@ void PEI::replaceFrameIndices(MachineBasicBlock *BB, MachineFunction &Fn, // use that target machine register info object to eliminate // it. TRI.eliminateFrameIndex(MI, SPAdj, i, - FrameIndexVirtualScavenging ? NULL : RS); + FrameIndexVirtualScavenging ? nullptr : RS); // Reset the iterator if we were at the beginning of the BB. if (AtBeginning) { @@ -765,7 +819,7 @@ void PEI::replaceFrameIndices(MachineBasicBlock *BB, MachineFunction &Fn, DoIncr = false; } - MI = 0; + MI = nullptr; break; } @@ -797,13 +851,14 @@ void PEI::scavengeFrameVirtualRegs(MachineFunction &Fn) { // We might end up here again with a NULL iterator if we scavenged a // register for which we inserted spill code for definition by what was // originally the first instruction in BB. - if (I == MachineBasicBlock::iterator(NULL)) + if (I == MachineBasicBlock::iterator(nullptr)) I = BB->begin(); MachineInstr *MI = I; - MachineBasicBlock::iterator J = llvm::next(I); - MachineBasicBlock::iterator P = I == BB->begin() ? - MachineBasicBlock::iterator(NULL) : llvm::prior(I); + MachineBasicBlock::iterator J = std::next(I); + MachineBasicBlock::iterator P = + I == BB->begin() ? MachineBasicBlock::iterator(nullptr) + : std::prev(I); // RS should process this instruction before we might scavenge at this // location. This is because we might be replacing a virtual register @@ -846,7 +901,7 @@ void PEI::scavengeFrameVirtualRegs(MachineFunction &Fn) { // spill code will have been inserted in between I and J. This is a // problem because we need the spill code before I: Move I to just // prior to J. - if (I != llvm::prior(J)) { + if (I != std::prev(J)) { BB->splice(J, BB, I); // Before we move I, we need to prepare the RS to visit I again. |